1. Field of the Invention
The present invention relates to a 3D-image pickup optical system used for a 3D-image pickup apparatus employing one of a digital camera, a video camera and a broadcasting camera, and to the 3D-image pickup apparatus. In particular, the present invention relates to a 3D-image pickup optical system used for a 3D-image pickup apparatus that takes right and left images of an object having a parallax with one camera through two image pickup lenses.
2. Description of the Related Art
Conventionally, various apparatuses have been proposed that take right and left images with a parallax for viewing the images as stereoscopic images. For instance, Japanese Patent Application Laid-Open No. 2000-019663 proposes a 3D-image pickup apparatus that takes right and left images with a parallax with one camera particularly through two image pickup lenses, and a zoom lens dedicated for 3D-image pickup.
In the conventional art disclosed in Japanese Patent Application Laid-Open No. 2000-019663, a stop is disposed nearer an object than a varying magnification unit is to suppress increase in front lens diameter, thereby securing a human binocular disparity (ca. 65 mm). However, the conventional art disclosed in Japanese Patent Application Laid-Open No. 2000-019663 has a problem of an increase in the f-number with zooming up, and further has problems of difficulty in achieving a wider angle and a higher varying magnification and difficulty in achieving an optical performance capable of being viewed in a HD image quality.